164 THE BUILDING OF EASTERN AUSTRALIA 



near Mt. Barney, shows that the idea that the formations 

 become progressively more and more folded as we go north 

 towards Xew Guinea is not without limitations. [15] 



(6) So little compression has there been since the 

 ushering in of the Mesozoic in Eastern Australia, that artesian 

 water is obtainable in Mezosoic rocks, but not in older rocks. 



(7) The Desert Sandstone is a volcanic ash deposit, 

 probably partly of late Cretaceous, partly of Tertiary age, 

 as suggested by Tennyson Woods. [9] 



The Brisbane and the Gympie Rocks. 



The veteran geologist of Queensland, Dr. Jack, classed 

 most of the unfossiliferous schists of Queensland with 

 the Gympie formation. In my paper, " The Metamorphic 

 Rocks of Southern Queensland" [14], read before the 

 A.A.A.S., Brisbane Meeting, 1909, I gave some weighty 

 reasons for regarding the Gympie area as a small subsidence 

 area, in which, by reason of depression and compression 

 between adjoining blocks of the earth's crust, more recent 

 formations were metamorphosed than in the more elevated 

 blocks. Mr. Wearne's interesting discovery of Fenestella, 

 near Mt. Barney, in almost horizontal sandstones confirms 

 this view. [15j 



I am inclined to regard the unfossiliferous Palaeozoic 

 beds between Brisbane and Coff's Harbour, and also those 

 north of Brisbane in the D'Aguilar Ranges, and further 

 north in the Yabba Ranges, etc., as a palseozoic complex 

 of deep sea deposits, ranging from, perhaps, Pre-Cambrian to 

 Devonian or Carboniferous in age. These beds were 

 elevated in late Carboniferous or Permian times, and 

 portions of the area which they covered were submerged 

 again by an epicontinental sea, when the great Mesozoic 

 uplift of New England took place. The Clarence basin 

 sandstones and Ips^\'ich coal- measures were laid down in 

 this epicontinental sea. 



The Gympie beds of Gympie proper have been proved 

 by their fossil contents to be equivalent with the Lower 

 Marine beds of New South Wales, therefore Permo- Carboni- 

 ferous. While it is not only possible, but probable, that 

 large areas of Queensland were under shallow water in 

 Permo- Carboniferous times, the beds laid down in that 

 period have only been preserved in cases where they have 

 been downthrown by trough faulting. [14] 



